This invention relates to the functionalization of polyphenylene ethers (PPE) with graftable ethylenically unsaturated monomers, and more particularly ethylenically unsaturated orthoester (OE) monomers, and preferably to a method for grafting orthoester functionality onto polyphenylene ethers by a melt grafting process.
Orthoester bearing chlorotriazines have been used as capping agents for solution capping of polyphenylene ethers. The orthoester end-capped polyphenylene ethers are known to be effective compatibilizers of polyphenylene ether (PPE)/polyester blends. The method of the present invention allows the formation of novel polyphenylene ethers bearing grafted orthoester groups (PPE-g-OE). Further, the method of this invention eliminates the need for solution chemistry thereby reducing the intermediate steps thereby resulting in a more efficient process and eliminating the risk of environmentally unsound solvent usage.
The synthesis of various graftable and copolymerizable monomers bearing orthoester functionality and their use in the synthesis of the orthoester-functionalized polyolefins by melt grafting have been previously described. Reference is made, for example, to Ser. No. 07/645,179, now U.S. Pat. No. 5,171,866, and Ser. No. 07/716,157, now U.S. Pat. No. 5,153,290. The current invention produces novel functionalized polyphenylene ethers by grafting orthoester bearing monomers to polyphenylene ethers and preferably these novel functionalized polyphenylene ethers are produced in an all melt process.